<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"/>
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"/>
    <meta name="format-detection" content="telephone=no,email=no,date=no,address=no"/>
    <title>双向绑定原理</title>
</head>
<body>
<input type="text" />
<span id="text"></span>
<script>
    var text=document.getElementById("text");
    var data={};
    var value="";
    Object.defineProperty(data,"name",{
        get(){
            return value;
        },
        //监听数据发生变化
        set(val){
            // console.log(val);
            text.innerHTML=val;
            value=val;
        }
    });
    window.addEventListener("input",function(e){
        // console.log(e.target.value);
        data.name=e.target.value;
        console.log(data.name);
    })
</script>
</body>
</html>
